1. Field of the Invention
The present invention generally relates to an automatic ice making machine and, more particularly, to a coupling structure for connecting together an ice making unit and an ice storage or stocker in a stack-on type automatic ice making machine.
2. Description of the Prior Art
There is known such an ice making machine which is adapted to continuously manufacture ice blocks such as prismatic ice pellets by making use of an ice making mechanism. In that case, the amount of the ice as manufactured does not generally coincide with that of water consumed for making the ice. Under the circumstances, a stocker is used in combination with the ice making machine for storing the ice pellets as manufactured until they are used. In this regard, although the ice making mechanism is intrinsically imparted with a self-cooling function, the stocker lacks such cooling capability. According, the stocker has to be implemented in a heat insulating structure for preventing heat conduction from the exterior. For this reason, the ice making unit and the stocker are initially manufactured as separate components and finally assembled together by stacking the ice making mechanism on the stocker or vice versa. The ice making machine of this structure is referred to as the stack-on type ice making machine.
Heretofore, the stocker is constituted by using inner and outer boxes each made of a sheet metal or alternatively an inner box made of a resin and an outer box of a sheet metal, wherein a hollow space defined between both the boxes is filled with a heat insulating material in either case. For rigidly interconnecting the stocker with an ice making unit accommodating therein an ice making mechanism, nuts or the like clamping parts are used and secured by welding to the metal sheet casing of the ice making unit and the outer box of the stocker, wherein the ice making unit and the stocker are fixedly connected together by means of coupling plates.
When the outer box is made of a sheet metal, attachment of the nuts by welding or the like means as well as formation of threaded holes can be carried out relatively simply and easily while ensuring dimensional tolerance and mechanical strength as required, whereby the interconnection or coupling of both units can be realized satisfactorily.
However, when the inner and outer boxes of the stocker are formed integral with each other in an effort to reduce the manufacturing cost, difficulty is encountered in attaching the nuts or the like clamping parts and formation of the threaded holes when considering the molding die to be used to this end and the strength of the resin material.
Thus, there exists a demand for an coupling structure for connecting together the stocker and the ice making unit disposed thereon without need for forming threaded holes or attaching nuts to the stocker while ensuring a sufficient mechanical strength.